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            <p>
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    <div class='section' id='section-0'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-0'>#</a>
            </div>
            <h1>GPT-2 with <a href="index.html">LoRA modules</a></h1>
<p>Here&#x27;s <a href="experiment.html">the training code</a> for training a GPT2 model with LoRA  on Tiny Shakespeare dataset.</p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">13</span><span></span><span class="kn">import</span> <span class="nn">torch</span>
<span class="lineno">14</span><span class="kn">import</span> <span class="nn">torch.nn</span> <span class="k">as</span> <span class="nn">nn</span>
<span class="lineno">15</span>
<span class="lineno">16</span><span class="kn">from</span> <span class="nn">labml_nn.lora</span> <span class="kn">import</span> <span class="n">Linear</span><span class="p">,</span> <span class="n">Embedding</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-1'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-1'>#</a>
            </div>
            <h3>Feedforward Network</h3>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">19</span><span class="k">class</span> <span class="nc">FFN</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-2'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-2'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">d_model</span></code>
  is the number of dimensions </li>
<li><code  class="highlight"><span></span><span class="n">d_ff</span></code>
  is the size of the hidden dimension </li>
<li><code  class="highlight"><span></span><span class="n">r</span></code>
  is the lora rank</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">24</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">d_model</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">d_ff</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">r</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-3'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-3'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">30</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-4'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-4'>#</a>
            </div>
            <p>The linear layers and the activation </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">33</span>        <span class="bp">self</span><span class="o">.</span><span class="n">linear_in</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">d_ff</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="lineno">34</span>        <span class="bp">self</span><span class="o">.</span><span class="n">linear_out</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">d_ff</span><span class="p">,</span> <span class="n">d_model</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="lineno">35</span>        <span class="bp">self</span><span class="o">.</span><span class="n">act</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">GELU</span><span class="p">()</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-5'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-5'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">x</span></code>
  is the embeddings tensor with shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">37</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">x</span><span class="p">:</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">:</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-6'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-6'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">41</span>        <span class="n">x</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">linear_in</span><span class="p">(</span><span class="n">x</span><span class="p">)</span>
<span class="lineno">42</span>        <span class="n">x</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">act</span><span class="p">(</span><span class="n">x</span><span class="p">)</span>
<span class="lineno">43</span>        <span class="n">x</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">linear_out</span><span class="p">(</span><span class="n">x</span><span class="p">)</span>
<span class="lineno">44</span>        <span class="k">return</span> <span class="n">x</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-7'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-7'>#</a>
            </div>
            <h3>Multi-Head Attention</h3>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">47</span><span class="k">class</span> <span class="nc">MultiHeadAttention</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-8'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-8'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">d_model</span></code>
  is the number of dimensions in the embeddings </li>
<li><code  class="highlight"><span></span><span class="n">n_heads</span></code>
  is the number of heads </li>
<li><code  class="highlight"><span></span><span class="n">r</span></code>
  is the lora rank</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">52</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">d_model</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">n_heads</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">r</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-9'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-9'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">58</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span>
<span class="lineno">59</span>        <span class="bp">self</span><span class="o">.</span><span class="n">d_model</span> <span class="o">=</span> <span class="n">d_model</span>
<span class="lineno">60</span>        <span class="bp">self</span><span class="o">.</span><span class="n">n_heads</span> <span class="o">=</span> <span class="n">n_heads</span>
<span class="lineno">61</span>        <span class="bp">self</span><span class="o">.</span><span class="n">d_head</span> <span class="o">=</span> <span class="n">d_model</span> <span class="o">//</span> <span class="n">n_heads</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-10'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-10'>#</a>
            </div>
            <p>Linear transformation for QKV </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">64</span>        <span class="bp">self</span><span class="o">.</span><span class="n">qkv_projection</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">d_model</span> <span class="o">*</span> <span class="mi">3</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-11'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-11'>#</a>
            </div>
            <p>Output projection </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">66</span>        <span class="bp">self</span><span class="o">.</span><span class="n">output_projection</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">d_model</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-12'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-12'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">x</span></code>
  is the tensor with shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">68</span>    <span class="k">def</span> <span class="nf">_split_heads</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">x</span><span class="p">:</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-13'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-13'>#</a>
            </div>
            <p>Split last dimension to <code  class="highlight"><span></span><span class="p">[</span><span class="n">n_heads</span><span class="p">,</span> <span class="n">d_head</span><span class="p">]</span></code>
 </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">73</span>        <span class="n">x</span> <span class="o">=</span> <span class="n">x</span><span class="o">.</span><span class="n">view</span><span class="p">(</span><span class="n">x</span><span class="o">.</span><span class="n">shape</span><span class="p">[:</span><span class="o">-</span><span class="mi">1</span><span class="p">]</span> <span class="o">+</span> <span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">n_heads</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">d_head</span><span class="p">))</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-14'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-14'>#</a>
            </div>
            <p>Reorder to <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">head</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="n">d_head</span><span class="p">]</span></code>
 </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">75</span>        <span class="k">return</span> <span class="n">x</span><span class="o">.</span><span class="n">permute</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-15'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-15'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">x</span></code>
  is the embeddings tensor with shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">77</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">x</span><span class="p">:</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">:</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-16'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-16'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">81</span>        <span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="n">_</span> <span class="o">=</span> <span class="n">x</span><span class="o">.</span><span class="n">shape</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-17'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-17'>#</a>
            </div>
            <p>Get query, key and value </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">84</span>        <span class="n">q</span><span class="p">,</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">qkv_projection</span><span class="p">(</span><span class="n">x</span><span class="p">)</span><span class="o">.</span><span class="n">split</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">d_model</span><span class="p">,</span> <span class="n">dim</span><span class="o">=-</span><span class="mi">1</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-18'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-18'>#</a>
            </div>
            <p>Transform them from shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
 to <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">head</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="n">d_head</span><span class="p">]</span></code>
 </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">87</span>        <span class="n">q</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">q</span><span class="p">)</span>
<span class="lineno">88</span>        <span class="n">k</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">k</span><span class="p">)</span>
<span class="lineno">89</span>        <span class="n">v</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">_split_heads</span><span class="p">(</span><span class="n">v</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-19'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-19'>#</a>
            </div>
            <p>Apply causal attention </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">92</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="n">torch</span><span class="o">.</span><span class="n">nn</span><span class="o">.</span><span class="n">functional</span><span class="o">.</span><span class="n">scaled_dot_product_attention</span><span class="p">(</span><span class="n">q</span><span class="p">,</span> <span class="n">k</span><span class="p">,</span> <span class="n">v</span><span class="p">,</span> <span class="n">is_causal</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-20'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-20'>#</a>
            </div>
            <p>Transform them from shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">head</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="n">d_head</span><span class="p">]</span></code>
 to <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
 </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">95</span>        <span class="n">attn_output</span> <span class="o">=</span> <span class="n">attn_output</span><span class="o">.</span><span class="n">permute</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">1</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span><span class="o">.</span><span class="n">reshape</span><span class="p">(</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_length</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="n">d_model</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-21'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-21'>#</a>
            </div>
            <p>Final project </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">98</span>        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">output_projection</span><span class="p">(</span><span class="n">attn_output</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-22'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-22'>#</a>
            </div>
            <h3>Decoder block</h3>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">101</span><span class="k">class</span> <span class="nc">Block</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-23'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-23'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">d_model</span></code>
  is the number of dimensions in the embeddings </li>
<li><code  class="highlight"><span></span><span class="n">n_heads</span></code>
  is the number of heads </li>
<li><code  class="highlight"><span></span><span class="n">layer_norm_epsilon</span></code>
  is the layer norm epsilon </li>
<li><code  class="highlight"><span></span><span class="n">r</span></code>
  is the lora rank</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">106</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">d_model</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">n_heads</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">layer_norm_epsilon</span><span class="p">:</span> <span class="nb">float</span><span class="p">,</span> <span class="n">r</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-24'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-24'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">113</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-25'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-25'>#</a>
            </div>
            <p>Attention pre-normalization layer </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">115</span>        <span class="bp">self</span><span class="o">.</span><span class="n">attn_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">eps</span><span class="o">=</span><span class="n">layer_norm_epsilon</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-26'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-26'>#</a>
            </div>
            <p>Attention layer </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">117</span>        <span class="bp">self</span><span class="o">.</span><span class="n">attn</span> <span class="o">=</span> <span class="n">MultiHeadAttention</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">n_heads</span><span class="p">,</span> <span class="n">r</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-27'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-27'>#</a>
            </div>
            <p>FFN pre-normalization layer </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">119</span>        <span class="bp">self</span><span class="o">.</span><span class="n">ffn_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">eps</span><span class="o">=</span><span class="n">layer_norm_epsilon</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-28'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-28'>#</a>
            </div>
            <p>Feed-forward network </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">121</span>        <span class="bp">self</span><span class="o">.</span><span class="n">ffn</span> <span class="o">=</span> <span class="n">FFN</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">d_model</span> <span class="o">*</span> <span class="mi">4</span><span class="p">,</span> <span class="n">r</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-29'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-29'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">x</span></code>
  is the embeddings tensor with shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">,</span> <span class="n">d_model</span><span class="p">]</span></code>
</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">123</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">x</span><span class="p">:</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">:</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-30'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-30'>#</a>
            </div>
            <p>Attention </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">128</span>        <span class="n">x</span> <span class="o">=</span> <span class="n">x</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">attn</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">attn_norm</span><span class="p">(</span><span class="n">x</span><span class="p">))</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-31'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-31'>#</a>
            </div>
            <p>FFN </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">130</span>        <span class="n">x</span> <span class="o">=</span> <span class="n">x</span> <span class="o">+</span> <span class="bp">self</span><span class="o">.</span><span class="n">ffn</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="n">ffn_norm</span><span class="p">(</span><span class="n">x</span><span class="p">))</span>
<span class="lineno">131</span>
<span class="lineno">132</span>        <span class="k">return</span> <span class="n">x</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-32'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-32'>#</a>
            </div>
            <h2>GPT2 Model</h2>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">135</span><span class="k">class</span> <span class="nc">GPTModel</span><span class="p">(</span><span class="n">nn</span><span class="o">.</span><span class="n">Module</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-33'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-33'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">d_model</span></code>
  is the number of dimensions in the embeddings </li>
<li><code  class="highlight"><span></span><span class="n">n_heads</span></code>
  is the number of attention heads </li>
<li><code  class="highlight"><span></span><span class="n">n_layers</span></code>
  is the number of decoder layers </li>
<li><code  class="highlight"><span></span><span class="n">n_positions</span></code>
  is the number of positional embeddings </li>
<li><code  class="highlight"><span></span><span class="n">layer_norm_epsilon</span></code>
  is the layer norm epsilon </li>
<li><code  class="highlight"><span></span><span class="n">vocab_size</span></code>
  is the vocabulary size </li>
<li><code  class="highlight"><span></span><span class="n">r</span></code>
  is the lora rank</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">140</span>    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">*</span><span class="p">,</span> <span class="n">d_model</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span>
<span class="lineno">141</span>                 <span class="n">n_heads</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">n_layers</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span>
<span class="lineno">142</span>                 <span class="n">n_positions</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span>
<span class="lineno">143</span>                 <span class="n">layer_norm_epsilon</span><span class="p">:</span> <span class="nb">float</span><span class="p">,</span>
<span class="lineno">144</span>                 <span class="n">vocab_size</span><span class="p">:</span> <span class="nb">int</span><span class="p">,</span> <span class="n">r</span><span class="p">:</span> <span class="nb">int</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-34'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-34'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">154</span>        <span class="nb">super</span><span class="p">()</span><span class="o">.</span><span class="fm">__init__</span><span class="p">()</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-35'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-35'>#</a>
            </div>
            <p>Token and absolute positional embeddings </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">157</span>        <span class="bp">self</span><span class="o">.</span><span class="n">token_embedding</span> <span class="o">=</span> <span class="n">Embedding</span><span class="p">(</span><span class="n">vocab_size</span><span class="p">,</span> <span class="n">d_model</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">)</span>
<span class="lineno">158</span>        <span class="bp">self</span><span class="o">.</span><span class="n">position_embedding</span> <span class="o">=</span> <span class="n">Embedding</span><span class="p">(</span><span class="n">n_positions</span><span class="p">,</span> <span class="n">d_model</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-36'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-36'>#</a>
            </div>
            <p>Decoder blocks </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">161</span>        <span class="bp">self</span><span class="o">.</span><span class="n">blocks</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">ModuleList</span><span class="p">([</span><span class="n">Block</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">n_heads</span><span class="p">,</span> <span class="n">layer_norm_epsilon</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">)</span>
<span class="lineno">162</span>                                     <span class="k">for</span> <span class="n">_</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">n_layers</span><span class="p">)])</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-37'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-37'>#</a>
            </div>
            <p>Final layer norm </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">165</span>        <span class="bp">self</span><span class="o">.</span><span class="n">final_norm</span> <span class="o">=</span> <span class="n">nn</span><span class="o">.</span><span class="n">LayerNorm</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">eps</span><span class="o">=</span><span class="n">layer_norm_epsilon</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-38'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-38'>#</a>
            </div>
            <p>Projection layer to logit space </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">167</span>        <span class="bp">self</span><span class="o">.</span><span class="n">lm_head</span> <span class="o">=</span> <span class="n">Linear</span><span class="p">(</span><span class="n">d_model</span><span class="p">,</span> <span class="n">vocab_size</span><span class="p">,</span> <span class="n">r</span><span class="o">=</span><span class="n">r</span><span class="p">,</span> <span class="n">bias</span><span class="o">=</span><span class="kc">False</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-39'>
        <div class='docs doc-strings'>
            <div class='section-link'>
                <a href='#section-39'>#</a>
            </div>
            <ul><li><code  class="highlight"><span></span><span class="n">input_ids</span></code>
  has shape <code  class="highlight"><span></span><span class="p">[</span><span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span><span class="p">]</span></code>
</li></ul>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">169</span>    <span class="k">def</span> <span class="nf">forward</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">input_ids</span><span class="p">:</span> <span class="n">torch</span><span class="o">.</span><span class="n">Tensor</span><span class="p">):</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-40'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-40'>#</a>
            </div>
            
        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">173</span>        <span class="n">batch_size</span><span class="p">,</span> <span class="n">seq_len</span> <span class="o">=</span> <span class="n">input_ids</span><span class="o">.</span><span class="n">shape</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-41'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-41'>#</a>
            </div>
            <p>Get token embeddings </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">176</span>        <span class="n">token_embeddings</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">token_embedding</span><span class="p">(</span><span class="n">input_ids</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-42'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-42'>#</a>
            </div>
            <p>Get position ids </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">178</span>        <span class="n">position_ids</span> <span class="o">=</span> <span class="n">torch</span><span class="o">.</span><span class="n">arange</span><span class="p">(</span><span class="n">seq_len</span><span class="p">,</span> <span class="n">device</span><span class="o">=</span><span class="n">input_ids</span><span class="o">.</span><span class="n">device</span><span class="p">)[</span><span class="kc">None</span><span class="p">,</span> <span class="p">:]</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-43'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-43'>#</a>
            </div>
            <p>Get position embeddings </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">180</span>        <span class="n">position_embeddings</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">position_embedding</span><span class="p">(</span><span class="n">position_ids</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-44'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-44'>#</a>
            </div>
            <p>Add position embeddings </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">183</span>        <span class="n">x</span> <span class="o">=</span> <span class="n">token_embeddings</span> <span class="o">+</span> <span class="n">position_embeddings</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-45'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-45'>#</a>
            </div>
            <p>Run through transformer blocks </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">186</span>        <span class="k">for</span> <span class="n">block</span> <span class="ow">in</span> <span class="bp">self</span><span class="o">.</span><span class="n">blocks</span><span class="p">:</span>
<span class="lineno">187</span>            <span class="n">x</span> <span class="o">=</span> <span class="n">block</span><span class="p">(</span><span class="n">x</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-46'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-46'>#</a>
            </div>
            <p>Final normalization </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">190</span>        <span class="n">x</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">final_norm</span><span class="p">(</span><span class="n">x</span><span class="p">)</span></pre></div>
        </div>
    </div>
    <div class='section' id='section-47'>
        <div class='docs'>
            <div class='section-link'>
                <a href='#section-47'>#</a>
            </div>
            <p>Get logits from projection layer </p>

        </div>
        <div class='code'>
            <div class="highlight"><pre><span class="lineno">192</span>        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">lm_head</span><span class="p">(</span><span class="n">x</span><span class="p">)</span></pre></div>
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    }

    function handleImage(img) {
        img.parentElement.style.textAlign = 'center'

        var modal = document.createElement('div')
        modal.id = 'modal'

        var modalContent = document.createElement('div')
        modal.appendChild(modalContent)

        var modalImage = document.createElement('img')
        modalContent.appendChild(modalImage)

        var span = document.createElement('span')
        span.classList.add('close')
        span.textContent = 'x'
        modal.appendChild(span)

        img.onclick = function () {
            console.log('clicked')
            document.body.appendChild(modal)
            modalImage.src = img.src
        }

        span.onclick = function () {
            document.body.removeChild(modal)
        }
    }

    handleImages()
</script>
</body>
</html>